This invention pertains generally to motion converters and, more particularly, to a helical thruster for converting linear motion to rotary motion.
It is in general an object of the invention to provide a new and improved helical thruster for converting linear motion to rotary motion.
Another object of the invention is to provide a helical thruster of the above character which overcomes the limitations and disadvantages of the prior art.
These and other objects are achieved in accordance with the invention by providing a helical thruster comprising a housing with an axially extending bore, a piston movable axially within the bore between retracted and extended positions, means for applying a pressurized fluid to the piston to move the piston from the retracted position toward the extended position, an output member rotatively mounted on the housing, and a driving connection between the piston and the output member such that the output member rotates as the piston travels from the retracted position to the extended position. In one disclosed embodiment, the piston is non-rotating, and the driving connection is a helical drive which imparts rotation to the output member as the piston travels toward the extended position. In another, disclosed embodiment, the piston rotates as it travels toward the extended position, and the driving connection constrains the output member for rotation with the piston.